Notes

function declaration, function signature, function prototype
(Declaring/explicitly stating the function within the file)

function definition == what you do in the header file
(defining the entire function in that program)

so instead of doing function declaration within the file, you can declare that inside a header file then write the preprocessing file within the file
such as:

#include <stdio.h>
#include "myadd.h" => this part will be that header file declared as a pre-processing file

Difference between #include < > and #include " "
< > => this is telling your compiler to look into the system to find it (such as in the libraries)
" " => this is telling your compiler to look into the current directory to find it

printf statement located within the standard library file (libc.a)

One of C's deficiencies is that if you include an extra parameter in the .c file but forget to update the .h file, it will still compile and link fine, but obviously, it will give you the wrong output
In order to not make this mistake, you have to include the header file function declaration within the file so that when you are trying to compile, it will remind you to fix the header file and recompile


MEMORIZE***
2^8 = 256
2^9 = 512
2^10 = 1024
2^20 = 1024 * 1024 = about 1M
2^30 = 1024 * 1024 *1024 = about 1B --> which is 1GB in terms of computer memory